314 TEfiTIAET VEETEBEATA OF THE FATtTM. 



it slopes away on either side of a median ridge. Most of the upper surface is covered 

 with prominent tubercles, which show a tendency to arrangement in longitudinal rows. 

 Two double rows of especially large tubercles run on either side of the fontanelle, 

 converging in front of and behind it ; the opening itself is situated towards the front 

 of the skull and at the bottom of an elongated furrow, the sides of which are not 

 tuberculate. The supraoccipital does not project far behind the rest of the skull and 

 evidently united closely with the large interneural plate. The epiotic processes 

 project strongly backwards and outwards, and bear on their postero-inferior face an 

 elongated surface for union with the post-temporals. The ethmoid is broad, and its 

 anterior border nearly straight, so that the snout appears to be abruptly truncated. 

 The anterior complex vertebra is long and biconcave as usual ; its ventral surface is 

 deeply channelled for the dorsal aorta, and, in older specimens at least, the channel 

 is completely enclosed in its middle region. 



A pectoral spine, which probably belongs to this species, bears a row of transversely 

 elongated tubercles along its convex border and near its extremity ; the upper surface 

 also is tuberculate. 



Form. & Loc. — Qasr-el-Sagha beds (Middle Eocene) : north of Birket-el-Qurun. 



C. ]0197. Nearly complete skull. The dimensions (in centimetres) o£ this specimen are : — 



Length from basioccipital to tip of snout 325 



Greatest width at posterior end 16'4 app. 



„ „ anterior end 175 



C. 10198. Portion of skull-roof, well preserved posteriorly and showing the sculpture. 



P. 10340. Well-preserved skull, with anterior complex vertebra still united. The dimensions (in 

 centimetres) of this specimen are : — 



Length from basioccipital to tip of snout 32'4 



,, supraoccipital to tip of snout 36 



Greatest width at posterior end 20 app. 



„ „ anterior end 19"4 



Length of complex vertebra 10'8 



Presented hy the Egyptian Government, 1904. 



P. 10250. Posterior half of a skull. The greatest width at the posterior end is 16 cm. 



Presented hy Baron Nopcsa, 1905. 



P. 10251. Portions o£ two similar skulls. Presented hy Baron Nopcsa, 1905. 



P. 10245. Portion of skull, in which the sculpture of the roofing-bones is well shown. 



